catrafter
Marantz Specialist
Are the plugs on the PX01 board installed correctly?
Check J702 on the power amps, too.
Tom
Marantz 2500 on the bench
- Thread starter mikey99
- Start date
Are the plugs on the PX01 board installed correctly?
Check J702 on the power amps, too.
Tom
mikey99
Active Member
Thanks, those plugs all look okay. I printed out the PX01 schematic, it shows some of the expected voltages at various
points so I'll be checking those next. Strange that both LED's are on..... seems to indicate something common to both
channels. I found another forum post where one LED was always on, caused by a broken ground wire, but didn't say which wire.
mikey99
Active Member
Hmm, just noticed that the Peak LED's stay on for a few minutes ......when I turn the power switch off.......then slowly fade out.
Definitely looks like a grounding problem.........
I checked the ground to the PX01 board, which appears to be Pin 2 (black wire) on the large connector at the front of the board.
It runs down to a small terminal strip below the P800 board..... So I suspect the other black wire running from that terminal strip to the underside of the chassis may be broken somewhere.
Definitely looks like a grounding problem.........
I checked the ground to the PX01 board, which appears to be Pin 2 (black wire) on the large connector at the front of the board.
It runs down to a small terminal strip below the P800 board..... So I suspect the other black wire running from that terminal strip to the underside of the chassis may be broken somewhere.
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mikey99
Active Member
It's been a few years since I started this thread. After the initial repairs I made to
replace outputs and several other faulty components, the Marantz 2500 has been working
well. I've been listening to this on a regular basis, sometimes playing for several
hours at a time.
I've always had replacing the main filter capacitors on my todo list and recently
decided to tackle this. I debated re-stuffing the original cans or building a plate
and installing four individual capacitors. In the end I went with re-stuffing to
preserve the original look. I followed rBuckner's recipe, 4x(4x1800uf) Nichicon LGU2A182MELA.
For insulators I purchased acrylic disks 60mm diameter x 3mm thick. I also used rubber
circles I cut from a bicycle inner tube.
Caps removed:
Caps:
Using the $14 Harbor Freight 2.5 inch pipe cutter to open the cans:
Several arrays ready for wiring:
Wiring:
Wiring showing how the arrays will be stacked in the cans:
Showing how all the acrylic disk and rubber insulators will be placed:
In the can:
Wiring:
Final wiring including 2.2uf bypass capacitors:
replace outputs and several other faulty components, the Marantz 2500 has been working
well. I've been listening to this on a regular basis, sometimes playing for several
hours at a time.
I've always had replacing the main filter capacitors on my todo list and recently
decided to tackle this. I debated re-stuffing the original cans or building a plate
and installing four individual capacitors. In the end I went with re-stuffing to
preserve the original look. I followed rBuckner's recipe, 4x(4x1800uf) Nichicon LGU2A182MELA.
For insulators I purchased acrylic disks 60mm diameter x 3mm thick. I also used rubber
circles I cut from a bicycle inner tube.
Caps removed:
Caps:
Using the $14 Harbor Freight 2.5 inch pipe cutter to open the cans:
Several arrays ready for wiring:
Wiring:
Wiring showing how the arrays will be stacked in the cans:
Showing how all the acrylic disk and rubber insulators will be placed:
In the can:
Wiring:
Final wiring including 2.2uf bypass capacitors:
mikey99
Active Member
Showing how the terminal end is installed with the wires passing through:
Finally back up and running with new main filter caps.
Changed all tuning panel lights to soft white LED's.
Changed all the source input LED indicators to green (special LED's purchased from Mouser)
Also replaced the two red Peak indicators with new LED's:
Finally back up and running with new main filter caps.
Changed all tuning panel lights to soft white LED's.
Changed all the source input LED indicators to green (special LED's purchased from Mouser)
Also replaced the two red Peak indicators with new LED's:
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Steven Tate
CEO Flat Forehead Soc.
Very nice work. Can you hear a difference?
mikey99
Active Member
Sounds exactly the same to me
I didn't expect to hear any difference..... although it's possible the bass might improve somewhat
under heavy load conditions. After seeing all the fun everyone was having cutting these capacitors
open I just had to experience this for myself ! Hopefully the new caps will increase the reliability.
This was the last thing on my todo list for this receiver.
Last edited:
Steven Tate
CEO Flat Forehead Soc.
Haha. I’m kind of in that spot with a 2245 right now (discussing it in another thread). I planned to do a complete rebuild, but when I checked it out, it sounds so good, I’m having to pull the reins in and deal with surface things like lamps. I’m pretty sure if I recapped this one, it wouldn’t improve the sound. And that’s a rarity for me. Most of these that I pick up are not sounding their best. Your 2500 is beautiful. Very nice work!Sounds exactly the same to me
I didn't expect to hear any difference..... although it's possible the bass might improve somewhat
under heavy load conditions. After seeing all the fun everyone was having cutting these capacitors
open I just had to experience this for myself ! Hopefully the new caps will increase the reliability.
This was the last thing on my todo list for this receiver.
Yep, that's the fan to use! Thanks to @catrafter for that recommendation years ago... Congrats on the work, the 2500 isn't for the faint of heart, or arm/chest/back muscles.